package com.lt.app;

import android.annotation.SuppressLint;
import android.content.Context;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.content.pm.PackageManager.NameNotFoundException;
import android.os.Looper;
import android.util.Log;
import android.widget.Toast;

import com.lt.common.FileHelper;

import java.io.File;
import java.io.FileOutputStream;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.io.Writer;
import java.lang.Thread.UncaughtExceptionHandler;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;

/**
 * UncaughtException处理类,当程序发生Uncaught异常的时候,有该类来接管程序,并记录发送错误报告.
 * <p>
 * <p>
 * 在Application的onCreat里面声明调用
 * <p>
 * CrashHandler.getInstance().init(this);
 *
 * @author luotian
 */

public class CrashHandler implements UncaughtExceptionHandler {

    public static final String TAG = "CrashHandler";

    // 系统默认的UncaughtException处理类
    private UncaughtExceptionHandler mDefaultHandler;
    // CrashHandler实例
    @SuppressLint("StaticFieldLeak")
    private static CrashHandler instance;
    // 程序的Context对象
    protected Context mContext;
    // 用来存储设备信息和异常信息
    private Map<String, String> infos = new HashMap<>();

    // 用于格式化日期,作为日志文件名的一部分
    private final DateFormat formatter = new SimpleDateFormat("yyyy-MM-dd-HH-mm");

    /**
     * 保证只有一个CrashHandler实例
     */
    protected CrashHandler() {
    }

    /**
     * 获取CrashHandler实例 ,单例模式
     */
    public static CrashHandler getInstance() {
        if (instance == null) {
            synchronized (CrashHandler.class) {
                instance = new CrashHandler();
            }
        }
        return instance;
    }

    /**
     * 初始化
     */
    public void init(Context context) {
        mContext = context;
        // 获取系统默认的UncaughtException处理器
        mDefaultHandler = Thread.getDefaultUncaughtExceptionHandler();
        // 设置该CrashHandler为程序的默认处理器
        Thread.setDefaultUncaughtExceptionHandler(this);
    }

    /**
     * 当UncaughtException发生时会转入该函数来处理
     */
    @Override
    public void uncaughtException(Thread thread, Throwable ex) {
        if (!handleException(ex) && mDefaultHandler != null) {
            // 如果用户没有处理则让系统默认的异常处理器来处理
            mDefaultHandler.uncaughtException(thread, ex);
        } else {
            try {
                Thread.sleep(3000);
            } catch (InterruptedException e) {
                Log.e(TAG, "error : ", e);
            }
            handleResult();
        }
    }

    /**
     * 自定义错误处理,收集错误信息 发送错误报告等操作均在此完成.
     *
     * @param ex 异常
     * @return true:如果处理了该异常信息;否则返回false.
     */
    private boolean handleException(Throwable ex) {
        if (ex == null) {
            return false;
        }
        // 使用Toast来显示异常信息
        new Thread() {
            @Override
            public void run() {
                Looper.prepare();
                Toast.makeText(mContext, "抱歉，程序出现异常",
                        Toast.LENGTH_LONG).show();
                Looper.loop();
            }
        }.start();
        // 收集设备参数信息
        collectDeviceInfo();
        // 保存日志文件
        saveCrashInfo2File(ex);
        return true;
    }

    public File getLogDir() {
        File dir = FileHelper.getInstance().getSDPath();
        if (dir == null) {
            dir = mContext.getCacheDir();
        }
        dir = new File(dir, "ALT");
        if (!dir.exists()) {
            dir.mkdir();
        }
        return dir;
    }

    /**
     * @return 返回日志存储的文件
     */
    protected File getLogFile() {
        File dir = getLogDir();
        String time = formatter.format(new Date());
        String fileName = "crash-" + time + ".log";
//        String fileName = "crash.log";
        File file = new File(dir, fileName);
        if (file.exists()) {
            file.delete();
        }
        return file;
    }

    /**
     * 收集设备参数信息
     */
    private void collectDeviceInfo() {
        try {
            PackageManager pm = mContext.getPackageManager();
            PackageInfo pi = pm.getPackageInfo(mContext.getPackageName(),
                    PackageManager.GET_ACTIVITIES);
            if (pi != null) {
                String versionName = pi.versionName == null ? "null"
                        : pi.versionName;
                String versionCode = pi.versionCode + "";
                infos.put("versionName", versionName);
                infos.put("versionCode", versionCode);
            }
        } catch (NameNotFoundException e) {
            Log.e(TAG, "an error occured when collect package info", e);
        }
//        Field[] fields = Build.class.getDeclaredFields();
//        for (Field field : fields) {
//            try {
//                field.setAccessible(true);
//                infos.put(field.getName(), field.get(null).toString());
//            } catch (Exception e) {
//                Log.e(TAG, "an error occured when collect crash info", e);
//            }
//        }
    }

    /**
     * 保存错误信息到文件中
     *
     * @param ex 异常
     */
    private void saveCrashInfo2File(Throwable ex) {
        StringBuilder sb = new StringBuilder();
        for (Map.Entry<String, String> entry : infos.entrySet()) {
            String key = entry.getKey();
            String value = entry.getValue();
            sb.append(key).append("=").append(value).append("\r\n");
        }

        Writer writer = new StringWriter();
        PrintWriter printWriter = new PrintWriter(writer);
        ex.printStackTrace(printWriter);
        Throwable cause = ex.getCause();
        while (cause != null) {
            cause.printStackTrace(printWriter);
            cause = cause.getCause();
        }
        printWriter.close();
        String result = writer.toString();
        sb.append(result);
        try {
            File file = getLogFile();
            FileOutputStream fos = new FileOutputStream(file);
            fos.write(sb.toString().getBytes());
            fos.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }


    /**
     * 最后的处理
     * 可以退出或者重启等等
     * 默认退出
     * 重启可以用ProcessPhoenix框架
     * implementation 'com.jakewharton:process-phoenix:2.1.2'
     * ProcessPhoenix.triggerRebirth(mContext);
     */
    protected void handleResult() {
        // 退出程序
        android.os.Process.killProcess(android.os.Process.myPid());
        System.exit(1);
    }
}
